The Canadian Shield extends from Baffin Land to the east of the Coronation Gulf in the west, fell in the center to the Hudson Bay, and rises in the northeast border of Labrador, in the Laurentian and North the upper lake. Structural element is the oldest in North America. It retains traces of the Quaternary glaciers, moraines materials at the edges. To the west lies the Plain of San Lorenzo, last outpost of the shield.

Prairie Plains tip moving in between the shield and the Rocks. Its hydrography is uneven because of the sedimentary layers that form reliefs costs more or less covered with glacial deposits. These hills form three successive platforms: the plains of Manitoba, or low prairie, the plains of Saskatchewan, or Prairie middle and high plains of Alberta and Prairie.

Mountain West, younger than the East, rose in scundario and early Tertiary (Mount Robson 3954 meters).